Premium
Unprecedented Selectivity of Ruthenium Iodide Benzylidenes in Olefin Metathesis Reactions
Author(s) -
Nechmad Noy B.,
Phatake Ravindra,
Ivry Elisa,
Poater Albert,
Lemcoff N. Gabriel
Publication year - 2020
Publication title -
angewandte chemie
Language(s) - English
Resource type - Journals
eISSN - 1521-3757
pISSN - 0044-8249
DOI - 10.1002/ange.201914667
Subject(s) - dicyclopentadiene , ruthenium , chemistry , metathesis , olefin fiber , ring opening metathesis polymerisation , romp , salt metathesis reaction , alkene , grubbs' catalyst , olefin metathesis , iodide , acyclic diene metathesis , catalysis , combinatorial chemistry , organic chemistry , polymerization , polymer
Abstract The development of selective olefin metathesis catalysts is crucial to achieving new synthetic pathways. Herein, we show that cis ‐diiodo/sulfur‐chelated ruthenium benzylidenes do not react with strained cycloalkenes and internal olefins, but can effectively catalyze metathesis reactions of terminal dienes. Surprisingly, internal olefins may partake in olefin metathesis reactions once the ruthenium methylidene intermediate has been generated. This unexpected behavior allows the facile formation of strained cis ‐cyclooctene by the RCM reaction of 1,9‐undecadiene. Moreover, cis ‐1,4‐polybutadiene may be transformed into small cyclic molecules, including its smallest precursor, 1,5‐cyclooctadiene, by the use of this novel sequence. Norbornenes, including the reactive dicyclopentadiene (DCPD), remain unscathed even in the presence of terminal olefin substrates as they are too bulky to approach the diiodo ruthenium methylidene. The experimental results are accompanied by thorough DFT calculations.